Short peptides are poorly immunogenic when delivered sublingually - under the tongue. Nanomaterial delivery of peptides could be utilized to improve immunogenicity towards designed sublingual vaccines, but nanomaterials have not been widely successful in sublingual vaccines owing to the challenges of transport through the sublingual mucosa. Here, we report that the sublingual immunogenicity of peptides is negligible, even in the presence of sublingual adjuvants or when PEGylated, but can be dramatically enhanced by assembly into supramolecular polymer-peptide nanofibers bearing low-molecular weight PEG, optimally between 2000 and 3000 Da. Neither PEGylation nor a sublingual adjuvant were capable of rendering peptides immunogenic without assembly into nanofibers. We found that PEG decreased nanofiber interactions with mucin and promoted longer residence time at the sublingual immunization site. Parallel investigations with shortened nanofibers indicated that the size of the assemblies had a surprisingly negligible influence over sublingual immunogenicity. In mice, optimized formulations were capable of raising strong and highly durable systemic antibody responses, antibodies in the upper respiratory and reproductive tracts, and systemic antigen-specific T-cell responses. These nanofiber-based sublingual vaccines were effective with both protein and nucleotide adjuvants and raised responses against both a model peptide epitope and a peptide epitope from M. tuberculosis. Further, PASylation (modification of nanofibers with peptide sequences rich in Pro, Ala, and Ser) could be substituted for PEGylation to also achieve sublingual immunogenicity. These findings indicated that surface properties supersede nanomaterial size in modulating sublingual nanomaterial immunogenicity, having important implications for the design of synthetic sublingual vaccines.

中文翻译：

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通过分子自组装实现舌下肽免疫。

短肽在舌下通过舌下递送时免疫原性较差。肽的纳米材料递送可用于改善针对设计的舌下疫苗的免疫原性，但是由于通过舌下粘膜运输的挑战，纳米材料在舌下疫苗中尚未广泛成功。在这里，我们报告说，即使在存在舌下佐剂或聚乙二醇化的情况下，肽的舌下免疫原性也可以忽略不计，但是通过组装成携带低分子量PEG（最好在2000和3000 Da之间）的超分子聚合物-肽纳米纤维可以显着增强肽的舌下免疫原性。 。聚乙二醇化或舌下佐剂都不能在不组装成纳米纤维的情况下使肽具有免疫原性。我们发现PEG减少了纳米纤维与粘蛋白的相互作用，并促进了在舌下免疫部位的更长停留时间。对缩短的纳米纤维的并行研究表明，组件的大小对舌下免疫原性的影响令人惊讶地忽略不计。在小鼠中，优化的制剂能够引起强而高度持久的全身抗体应答，上呼吸道和生殖道中的抗体以及全身性抗原特异性T细胞应答。这些基于纳米纤维的舌下疫苗对蛋白质和核苷酸佐剂均有效，并且提高了对模型肽表位和结核分枝杆菌的肽表位的反应。此外，PASylation（用富含Pro，Ala，（Ser）和Ser）可以代替PEG化以也获得舌下免疫原性。这些发现表明，在调节舌下纳米材料的免疫原性方面，表面性质取代了纳米材料的大小，这对合成舌下疫苗的设计具有重要意义。